1. Field of the Invention
This invention generally relates to a reader-printer apparatus for viewing and printing microimages, such as microimages of computer data, disposed on microfiche and the like and in particular to an apparatus having a viewer and a slit exposure type image recording device which is particularly adapted to printing microimages lengthwise onto standard recording size paper from microfiche having a plurality of frames wherein the major axis of each frame is oriented transversely.
2. Description of the Prior Art
Various reader-printer apparatus are known in the art. Examples of such apparatus are disclosed in U.S. Pat. Nos. 4,310,241; 4,367,033; 4,447,147 and 4,593,996. In general, these apparatus are adapted to receive text, data, drawings or other information which have been recorded on microfiche, microfilm, aperture cards and the like and display the information on a viewing screen and, if desired, record the information on a suitable recording medium. Both full exposure and slit exposure type image recording apparatus are known. In general, in an apparatus having a full exposure type printer, the entire image is formed on the recording medium at one time. An example of such a system is disclosed in U.S. Pat. No. 4,593,996 to Kubono, et al. In a slit exposure type image recording apparatus, the image is formed on the recording medium in sections by scanning consecutive portions of the object being reproduced. The scanning speed in such a device must be synchronized with the rate at which the image is being recorded.
Two types of slit exposure type image recording apparatus are known in the art. Either a fixed optical system or a moving optical system may be utilized to form the image in consecutive portions on the recording medium. Fixed optical type systems are particularly suited for use with aperture cards. In such a system, the optical system is stationary and the original object is moved relative to the optical system. An example of such a system is disclosed in U.S. Pat. No. 4,310,241 to Inoue wherein a movable aperture card carriage is utilized. The fixed optical system includes a fixedly mounted lamp, lens, a vertically oriented slit and a mirror. Light rays from the lamp are projected through the lens and vertically oriented slit to project a portion of the image on the aperture card onto a mirror which reflects the rays onto a drum for recording an image on a recording medium. The object plane is defined by the aperture card and is generally perpendicular to the incident light rays from the lamp. In any given position of the aperture card with respect to the incident light rays, an image corresponding to a vertical slice of the object is formed on the recording medium. Thus, by moving the aperture card in a direction perpendicular to the incident light rays, the object can be consecutively formed on the recording medium.
In an apparatus having a moving optical system, the object is maintained in a stationary position and at least a portion of optical system is moved relative to the object in order to provide scanning by redirecting the projected image. This type of system is adapted for use with microfiche, aperture cards, microfilm, and the like. U.S. Pat. No. 4,367,033 to Wanatabe discloses such a system. In general, microfiche is placed in a carrier which maintains it in a fixed position relative to the optical system. Through the use of a slit member, the optical system projects a portion of the image at a time onto the recording medium. By moving at least a portion of the optical system relative to the object, the entire image is formed on the recording medium. More specifically, the original object recorded on microfiche is placed in a carriage defining an object plane. A source of light and a lens are arranged with respect to the microfiche such that the light rays are generally perpendicular to the image. The emergent light rays from the lens are reflected from movable mirrors onto a recording medium. The movable mirrors are carried by a scanning apparatus adapted to move along a plane which is generally perpendicular to the emergent light rays. The scanning apparatus carries a mirror at each end. When the scanning apparatus moves in a direction perpendicular to the emergent light rays from the lens, consecutive portions of the image are formed on the recording medium.
In both the full exposure and slit exposure type printing apparatus that have viewers, the system can only be operated in one mode at a time - either in a viewing mode or a printing mode. Generally, mirrors utilized in the system are associated with either the viewing mode or the printing mode. In order to avoid an unnecessarily complicated optical system and to avoid interference of the light rays between the viewing mode mirrors and print mode mirrors, some of the mirrors are pivotably mounted and swing out of the way when the system is operated in a mode in which the mirror is not used. For example, in the print mode one or more viewing mirrors may be made to swing out of the print mode optical path.
All of the aforementioned prior art reader-printer apparatus are adapted to receive microfiche and the like having a plurality of frames wherein the major axis of each frame is oriented vertically as shown in FIG. 1a. However, such apparatus will not perform satisfactorily with microfiche or the like wherein the major axis of the frames is oriented transversely as shown in FIG. 1b. Microfiche having frames oriented as depicted in FIG. 1b are generally used for computer data, which have been microfilmed from so-called "green bar" computer paper. Since green bar paper is generally 14 inches across by 11 inches long with the data printed parallel to the 147/8-inch edge, it is desirable to print images from such paper onto standard 81/2-inch by 11-inch paper such that the data is parallel to the 11-inch edge of the recording paper to avoid having a portion of the data cut off. In the aforedescribed prior art apparatus, in order to print such computer data recorded on microfiche having frames with the major axis oriented transversely as in FIG. 1 b, the original image would have to be transposed orthogonally. In some known prior art reader-printer apparatus the object is transposed manually. In the apparatus disclosed in U.S. Pat. No. 3,907,418 to Okuyama, a prism is used to transpose the image in the printing mode. However, manually transposing the object would be unduly cumbersome for a machine used primarily for printing copies of microfiche wherein the major axis of each of the frames is oriented transversely. Moreover, the addition of the prism to the apparatus complicates the optics within the apparatus.